Revolving-diffuser control-device for overhead space heating units



Jan. 12, 1965 Filed May 6, 1963 P. F. BRINEN 3,165,052 REVOLVING-DIFFUSER CONTROL-DEVICE FOR OVERHEAD SPACE HEATING um'rs 2 Sheets-Sheet 1 INVENTOR' PAUL F. BRINEN ATT'Y Jan. 12, 1965 P. F. BRINEN 3,155,052

REVOLV -DIFFUSER CONT DEVICE FOR 0V EAD SPACE HEAT UNITS Flled May 6, 1963 2 Sheets-Sheet 2 FIG. 3

INVENTOR' 35 PAUL F. BRINEN ATT'Y United States Patent 3,165,052 REVOLVENG-DIFFUSER CONTROL-DEVICE FOR ()VERHEAD SPACE HEATING UNITS Paul F. Brinen, Racine, Wis, assignor to Young Radiator Company, Racine, Wis, a corporation of Wisconsin Filed May 6, 1963, Ser. No. 278,354 1 Claim. (Cl. 98-4ti) This invention relates to a device for controlling a revolving diffuser suspended from an overhead fan-driven space-heater.

Fan-driven, overhead space heating units generally are of two types. One type has the fan located above the heating unit and blows down air through the heating unit for distribution over the space to be heated. The other type has the fan located below the heating unit and draws down air through the heating unit for distribution over the space to be heated.

In some of the larger sizes of such types of heating unit used for heating large, open building spaces, such as airplane hangars, angled diffusers are rotatively suspended from the heating unit whereby heated air is jetted outwardly over a large section of the space requiring heat. Where the diffuser is used with a blow down type of heating unit, it is necessary to provide a mechanism for revolving the diffuser at a predetermined speed to ensure the optimum of heating benefits. However, where the revolving diffuser is used with a draw-down heating unit it is imperative to provide some kind of mechanism for limiting the revolving of the diffuser to ensure the optimum of heating benefits.

The reason for having to provide such a control for a diffuser used with the draw-down type of heating unit is that the swirling air stream emitted by the fan, so directly adjacent the diffuser, impinges on the diffuser and causes it to revolve. Without some restraining control the diffuser would revolve at speeds much in excess of the strain that could be withstood by the supporting heating unit. Moreover, the speed of the unrestrained revolving diffuser would be much in excess of what is required for the optimum heating benefit for the space requiring heating.

The main objects of this invention, therefore, are: to provide an improved form of device for controlling the revolving of diffusers suspended from heating units of the type wherein the air-circulating fan is located below the heating unit so as to draw down the air through the heating unit; and to provide an improved device of this kind which is of such simple construction as to make its manufacture very economical, its attachment to the unit-heater and difiuser easily attained, and its control of the revolving diffuser highly eflicient.

In the adaptation shown in the accompanying drawmgs;

FIG. 1 is a perspective view of a draw-down type of unit-heater suspending a diffuser the revolving of which is controlled by a device constructed in accordance with this invention;

FIG. 2 is an enlarged elevation of the unit-heater, diffuser, and control device shown in FIG. 1;

FIG. 3 is a perspective view of the diffuser-revolving mounting whereto is attached a control device constructed in accordance with this invention;

FIG. 3A is an enlarged, fragmentary, view of a section of the diffuser mounting within the circle A of FIG. 2;

FIG. 4 is a much-enlarged, top view of the control device; and

FIG. 5 is a transverse sectional view of the device taken on the plane of the line 55 of FIG. 4.

The essential concept of this invention involves a 3,155,652 Patented Jan. 12, 1965 ice platform shiftably mounting a motor-driven-reductiongear unit for driving a small-diameter sheave, and yieldingly biased toward an outwardly-extended position on the platform, the platform being adapted for outwardlyextended mounting from the fan shroud of a draw-down type of overhead unit-heater journaling a suspended diffuser, whereby a belt embracive of the sheave and diffuser is tensioned, by the biased position of the reductiongear unit on the platform, to limit the revolutions of the diffuser to a predetermined number per minute.

A diffuser-revolving control device, adapted for attach ment to a unit-heater 6, of the type shown in Patent No. 2,812,925 suspending a conventional rotating diffuser 7, embodying the foregoing concept comprises a platform 8 whereon is shiftably mounted a motor-driven-reductiongear unit 9 biased by a spring 10 radially-outward from the unit-heater 6 to tension a belt 11 embracive of the diffuser 7 and a sheave 12 driven by the reduction-gear unit 9.

The hereinshown unit heater 6, for overhead suspension, in the heat-exchanger industry is referred to as a draw-down type for the reason that the fan-developed air current is drawn through rather than blown through the unit heater 6. Such a unit-heater comprises an annular coil 13 of finned tubes arranged between supporting plates 14 and 15 and having fixed thereon the respective inlet and outlet ports 16 and 17. The under plate 15 has an integrated, downwardly-extending, open annular extension generally designated as the shroud 18 for a fan 19. The fan 19 is rotatively suspended from and driven by a motor 20 mounted concentrically within the coil 13. The fan 19 being located below the coil 13 causes the air current to be drawn into the coil 13 mainly from the periphery thereof and down through the shroud 18 into the diffuser 7.

The diffuser 7, as hereinshown, is more or less a conventional construction. It comprises a journaling ring 21, a rotating ring 22 to the latter of which is secured a gusset-shaped transition 23 suspending a nozzle 24 to which is attached a deflector 25.

The journaling ring 21 is an annulus with an outwardlyextending flange 26 on its lower perimeter and is spanned by a series of radial spokes 27 secured to a journal bearing 28. The ring 21 is of a diameter to telescopically fit over the lower end of the fan shroud 18, to which it is secured by suitable fasteners 29, as later will be explained more fully. The journalling bearing 28 is of a form generally used for the rotative suspension of such diffusers.

The rotating ring 22, quite like the ring 21, is an annulus with an inwardly-extending flange 31 along its upper perimeter. The diameter of the ring 22 is somewhat larger than that of the ring 21 so that the upper perimeter of the ring 22 embraces the lower perimeter of the ring 21 with the flange 31 on the ring 22 extending inwardly over the outwardly-extending flange 26 on the ring 21 (FIG. 3A). The ring 22 also is embraced by an angle strip 33 serving as a guide seat for the belt 11 which connects the diffuser 7 to the hereinafter-described control device.

The gusset-shaped transition 23 may be secured to the ring 22 in any suitable manner, either by bonding or by the use of fasteners, such as rivets. The function, obviously, of the transition 23 is to dispose the axis of the nozzle 24 at an angle to that of the coil 13 and the rotating fan 19.

The nozzle 24 is a cylindrical fabrication generally with axially-disposed vanes 34. It is secured to the transition 23 by any suitable fasteners, and at its lower end has attached the deflector 25 which serves to jet the heated air stream, issuing from the nozzle 24, well out into'the area to be heated.

The fan I? is of the propeller type and is driven by the motor 26 at approximately 1140 rpm. In a propellertype fan the effective air flow area is from the inner edges of the blades to the outer perimeters thereof. From these blades the. downwardly-projected air stream comes off the fan blades in the form of an annular column. Moreover, such an annular column of air tends to swirl with the. rotation of the fan 1%. Such a swirling, annular air column impinges'directly against the transition 23 and is deflected downwardly into the nozzle 24. Were such a suspended revolving diffuser 7 unstrained it would tend to revolve at a speed of around 20 r.p.m. Such a speed would be too great not only for the structure to with :stand but unsafe for those who might have occasion to be in the area for which heat is required from such a heating unit. Therefore, such a control device, as now will be described, is an imperative accessory to limit the revolutions of the diffuser to a predetermined number per minute. For most practical purposes that limit should be between 1 and 2 revolutions per minute.

The platform 8 for the hereinshown control device, is a channel-shaped, sheet-metal stamping of frusto-pyrarnidical contour with the base end arcuate-shaped to permit bonding of the platform 3 to the fan-shroud-supported ring 21 to extend radially outward therefrom.

The motor-driven-reduction gear unit 9 is a very-compact standard stock item available on the open market. This particular unit comprises a H.P., 115 v. electric motor operating at 3450 rpm. The reduction-gearing is structured to drive a shaft 35 at approximately 18 rpm. This shaft 35 extends down through the platform 5 and has keyed thereto the sheave 12. This small l-LP. motor and the gearing are compactly arranged in a housing.

The reduction-gear unit is mounted on a plate 39, shiftably supported on the base 36 of the platform 8 by bolt, nut and washer fasteners 37 extending through a pair of aligned slots 38 in the base 36 of the platform 8.

These fasteners 37 are loose enough to permit shifting of the unit-supporting-plate 39 by a biasing-spring 10 to maintain a constant driving tension on the belt 11.

The spring it embraces a rod 46 fixed on one end to a lug 41 on the inner end of the plate 39. The opposite end of the rod is slidably guided by a bracket 42 fixed on the platform 8 intermediate the plate 39 and the arcuate edge of the base 36 of the platform 8.

Since motor 29 for driving the fan 19 generally is for use on a 220-volt circuit, a transformer 43 is mounted on the side of the platform 8 with suitable cables 44 and 45 for connection of thetransformer 43, respectively, to the 220-volt circuit for the motor 24) and to the 1l5-volt motor of the reduction-gear unit 9.

The belt 11 is the conventional V-type. It is dimensioned to embrace the ring 22 of the diffuser 7 and the sheave 12. The belt is retained in driving position on the ring 22 by the angle guide strip 33.

Revolving diffusers 7, with the attached control device, are factory packaged ready for alternative uses. One use would be for mounting the diffuser on a currently-shipped unit heater 6. The other use would be for mounting the diffuser on a previously-installed unit heater 6. For either circumstance, the shroud 18 of the unit heater 6 has circumferentially-spaced nuts, welded around the inner face of the ring 21 ready for the insertion of bolts 29 inserted through slots 47 formed in the ring 21. it is merely a matter of telescoping the ring 21 over the shroud 18 and inserting and tightening-up the bolts 29. After this the cable 44 would be connected to a junction box 48 on the motor 261 (FIG. 2). Operation of the unit heater Wouid result in the diffuser 7 revolving at a limited number of times per minute.

W'hen the diffuser 7 with control device is shipped for mounting on a previously-installed unit heater 6 it is necessary only to drill holes in the heater housing for leading the cable 44 into the junction box 43. The cable 4-iwould be connected to a junction box 48, and, with the placing of the belt 111, the control device would be ready to limit the revolutions of the diffuser 7 to the desired number per minute.

Variations and modifications in the details of structure and arrangement of the parts may be resorted to within the spirit and coverage of the appended claim.

i claim:

A heat exchanger of the overhead-unit-heater type comprising,

(a) an annular heating core,

having a fan shroud depending from the core and mounting a motor-driven fan rotably suspended within the shroud to draw-down air through the core, a revolving air diffuser journaled on and suspended from the shroud, a platform channel-shaped and having the side walls converg ing radially outward and having the larger end of arcuate shape and attached to the shroud and extending radially outward therefrom, and having slots formed therein radially of the shroud. a base plate having fasteners thereon and extending through the base-plate slots to slidably support the plate on the platform, a motor-driven-reduction-gear unit fixed on the plate and connected to a sheave below the under face of the platform, (1) a belt embracing the sheave and the air-diffuser, and (g) a spring means mounted on the platform urging the base plate and unit outwardly along the base plate slots to maintain driving tension on the belt for limiting the revolutions of the air diffuser to a predetermined number per minute.

References Cited by the Examiner UNITED STATES PATENTS 2,252,954 8/41 Wheeler 98-40 2,278,581 4/42 Dexter 9843 2,300,879 11/42 Eley 3l091 2,390,630 12/45 Wheeler 98-40 2,812,925 11/57 Young 9S40 ROBERT A. OLEARY, Primary Examiner. 

